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Dimensional Effects in CO_(2) Uptake and Compressive Strength of Pervious Concrete Subjected to CO_(2) Curing
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作者 ZHOU Wenjia LIU Lixi +3 位作者 ZHU Liangliang WANG Keying XIAO Hang CHEN Xi 《Journal of Wuhan University of Technology(Materials Science)》 2025年第3期728-740,共13页
The size effects were experimentally investigated and the underlying mechanism was analyzed.The results reveal that,as the specimen size increases,the interconnectivity of macropores slightly decreases.This in turn co... The size effects were experimentally investigated and the underlying mechanism was analyzed.The results reveal that,as the specimen size increases,the interconnectivity of macropores slightly decreases.This in turn constrains the diffusion of CO_(2) and moisture in the specimens,resulting in an increase in the discrepancy between the internal and external carbonation degrees.An increase in cement paste thickness simultaneously decreases the quantity,average size,and interconnectivity of macropores,lowering the diffusion efficacy of CO_(2) and moisture and exacerbating the overall heterogeneity in carbonation.Moreover,the gradual blockage of macropores leads to the emergence of localized ‘occluded zones’ with much lower carbonation degree.The reduction in aggregate size significantly alters the average diameter and connectivity of macropores,leading to notable change to overall non-uniformity.This study provides insight into improving the CO_(2) curing effect of pervious concrete products and developing uniform curing methods. 展开更多
关键词 carbonation curing pervious concrete dimensional effects CO_(2)uptake
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二维大片径Ti_(3)C_(2)T_(x)薄膜的制备及其电磁屏蔽性能
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作者 夏斌 喻莉 +5 位作者 罗志娟 王众 周娅玲 杨帆 张剑桥 程诗慧 《功能材料》 北大核心 2026年第2期109-114,共6页
二维Ti_(3)C_(2)T_(x)具有特殊的微观层状结构和良好的物理化学性能,被视为新型高效的电磁屏蔽材料。Ti_(3)C_(2)T_(x)薄膜是通过二维纳米片堆叠制备,因此单个Ti_(3)C_(2)T_(x)纳米片的性能和薄膜中片层排列的有序性都决定了Ti_(3)C_(2)... 二维Ti_(3)C_(2)T_(x)具有特殊的微观层状结构和良好的物理化学性能,被视为新型高效的电磁屏蔽材料。Ti_(3)C_(2)T_(x)薄膜是通过二维纳米片堆叠制备,因此单个Ti_(3)C_(2)T_(x)纳米片的性能和薄膜中片层排列的有序性都决定了Ti_(3)C_(2)T_(x)薄膜的电磁屏蔽性能。基于差速离心的方法,筛选并制备了二维大片径的Ti_(3)C_(2)T_(x)薄膜。利用X射线衍射仪、透射电子显微镜和扫描电子显微镜对Ti_(3)C_(2)T_(x)的化学组成、晶体结构和微观形貌进行表征,利用四探针测试仪和矢量网络分析仪研究了Ti_(3)C_(2)T_(x)的电导率和电磁屏蔽性能。结果表明,大片径Ti_(3)C_(2)T_(x)纳米片在薄膜中呈现规则有序排列,且6μm以上片径Ti_(3)C_(2)T_(x)薄膜的电导率可达1.62×10^(5)S/m,是小片径薄膜的1.5倍,其电磁屏蔽性能最高可达64.8 dB。同时,在薄膜厚度为11μm时具有4.3×10^(6)dB/m的单位厚度电磁屏蔽效能。 展开更多
关键词 二维纳米材料 Ti_(3)C_(2)T_(x) 有序排列 电磁屏蔽 导电性
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NaOH-Na_(2)SO_(3)协同预处理调控桉木孔隙结构及树脂改性性能研究
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作者 覃引鸾 庞小莉 +2 位作者 陈龙海 郑小蓉 龙大军 《森林防火》 2026年第1期137-144,共8页
针对人工林桉树(Eucalyptus spp.)木材密度高、微纤丝角大导致的干燥开裂率高及吸湿膨胀率大等问题,提出分步改性策略:1)采用NaOH—Na_(2)SO_(3)混合溶液预处理优化孔隙结构;2)通过三聚氰胺改性脲醛树脂(MUF)浸渍增强疏水性。以大花序桉... 针对人工林桉树(Eucalyptus spp.)木材密度高、微纤丝角大导致的干燥开裂率高及吸湿膨胀率大等问题,提出分步改性策略:1)采用NaOH—Na_(2)SO_(3)混合溶液预处理优化孔隙结构;2)通过三聚氰胺改性脲醛树脂(MUF)浸渍增强疏水性。以大花序桉(Eucalyptus cloeziana)和尾叶桉(Eucalyptus urophylla)为对象,以及压汞法等方法分析预处理对木材细胞壁孔隙结构、化学成分及树脂浸渍性能的影响。结果表明:3%~5%NaOH与Na_(2)SO_(3)(比例0.83)混合溶液预处理可脱除55%以上木质素,同时抑制纤维素氧化降解,孔隙率提升至50.60%(大花序桉)和42.83%(尾叶桉);树脂改性后木材抗吸水率(WRE)达63.71%,抗膨胀率(ASE)提高至67.42%,尺寸稳定性显著改善。研究揭示了预处理-树脂改性协同作用机制,为速生桉木高值化利用提供了理论支持与技术路径。 展开更多
关键词 桉木 NaOH—Na_(2)SO_(3)预处理 孔隙结构 树脂改性 尺寸稳定性
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Three-dimensionally ordered macroporous CeO_2/Al_2O_3-supported Au nanoparticle catalysts: Effects of CeO_2 nanolayers on catalytic activity in soot oxidation 被引量:5
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作者 Baofang Jin Yuechang Wei +5 位作者 Zhen Zhao Jian Liu Yazhao Li Renjie Li Aijun Duan Guiyuan Jiang 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第9期1629-1641,共13页
A series of catalysts consisting of three‐dimensionally ordered macroporous(3DOM)x‐CeO2/Al2O3‐supported Au nanoparticles(x=2,10,20,and40wt%)were successfully synthesized using a reduction‐deposition method.These c... A series of catalysts consisting of three‐dimensionally ordered macroporous(3DOM)x‐CeO2/Al2O3‐supported Au nanoparticles(x=2,10,20,and40wt%)were successfully synthesized using a reduction‐deposition method.These catalysts were characterized using scanning electron microscopy,the Brunauer‐Emmett‐Teller method,X‐ray diffraction,transmission electron microscopy,ultraviolet‐visible spectroscopy,and temperature‐programmed reduction by H2.Au nanoparticles of mean particle size5nm were well dispersed and supported on the inner walls of uniform macropores.The3DOM structure improved the contact efficiency between soot and the catalyst.An Al‐Ce‐O solid solution was formed in the multilayer support,i.e.,x‐CeO2/Al2O3,by the incorporation of Al3+ions into the CeO2lattice,which resulted in the creation of extrinsic oxygen vacancies.Strong interactions between the metal(Au)and the support(Ce)increased the amount of active oxygen species,and this promoted soot oxidation.The catalytic performance in soot combustion was evaluated using a temperature‐programmed oxidation technique.The presence of CeO2nanolayers in the3DOM Au/x‐CeO2/Al2O3catalysts clearly improved the catalytic activities in soot oxidation.Among the prepared catalysts,3DOM Au/20%CeO2/Al2O3showed high catalytic activity and stability in diesel soot oxidation. 展开更多
关键词 Three‐dimensionally ordered macroporous material Gold nanoparticle Multilayer support CeO2 nanolayer Soot combustion
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Rare earth metal modified three dimensionally ordered macroporous MnO_x-CeO_2 catalyst for diesel soot combustion 被引量:9
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作者 qing tang jun du +3 位作者 bin xie yu yang wenchong yu changyuan tao 《Journal of Rare Earths》 SCIE EI CAS CSCD 2018年第1期64-71,共8页
Three dimensionally ordered macroporous (3DOM) Ce-based catalysts were successfully prepared via a surfactant-assisted colloidal crystal template (CCT) route. The as-synthesized catalysts showed well- ordered stru... Three dimensionally ordered macroporous (3DOM) Ce-based catalysts were successfully prepared via a surfactant-assisted colloidal crystal template (CCT) route. The as-synthesized catalysts showed well- ordered structures with macropores and small interconnected pore windows. The Raman results indi- cate that the catalyst persists pure fluorite cubic phases until the molar ratio of Mn exceeds O.3, therefore MnOx particles form and impede the contact of the active site and the reagent and restraining soot combustion. The doping of Nd into MnOx-CeO2 enhances the catalytic activity because of increased oxygen vacancy, Mn4- content and stronger redox ability. Nd-doping also improves thermal stability of the catalyst due to less sintering and none phase separation after thermal aging. The flesh and aged Mno.3Ceo.6Ndo.lO2 catalysts show the maximum oxidation rate for soot at 331 and 355 ℃in the O2/N2 atmosphere, achieving a nearly 100% CO2 selectivity. 展开更多
关键词 Neodymium dopingMnOx-CeO2Oxygen vacanciesSoot combustionThermal aging performanceThree dimensionally ordered macroporousstructure
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Surface characteristics analysis of fractures induced by supercritical CO_(2)and water through three-dimensional scanning and scanning electron micrography 被引量:8
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作者 Hao Chen Yi Hu +4 位作者 Jiawei Liu Feng Liu Zheng Liu Yong Kang Xiaochuan Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2021年第5期1047-1058,共12页
Morphology of hydraulic fracture surface has significant effects on oil and gas flow,proppant migration and fracture closure,which plays an important role in oil and gas fracturing stimulation.In this paper,we analyze... Morphology of hydraulic fracture surface has significant effects on oil and gas flow,proppant migration and fracture closure,which plays an important role in oil and gas fracturing stimulation.In this paper,we analyzed the fracture surface characteristics induced by supercritical carbon dioxide(SC-CO_(2))and water in open-hole and perforation completion conditions under triaxial stresses.A simple calculation method was proposed to quantitatively analyze the fracture surface area and roughness in macro-level based on three-dimensional(3D)scanning data.In micro-level,scanning electron micrograph(SEM)was used to analyze the features of fracture surface.The results showed that the surface area of the induced fracture increases with perforation angle for both SC-CO_(2)and water fracturing,and the surface area of SC-CO_(2)-induced fracture is 6.49%e58.57%larger than that of water-induced fracture.The fractal dimension and surface roughness of water-induced fractures increase with the increase in perforation angle,while those of SC-CO_(2)-induced fractures decrease with the increasing perforation angle.A considerable number of microcracks and particle peeling pits can be observed on SC-CO_(2)-induced fracture surface while there are more flat particle surfaces in water-induced fracture surface through SEM images,indicating that fractures tend to propagate along the boundary of the particle for SC-CO_(2)fracturing while water-induced fractures prefer to cut through particles.These findings are of great significance for analyzing fracture mechanism and evaluating fracturing stimulation performance. 展开更多
关键词 Supercritical carbon dioxide(SC-CO_(2))fracturing Quantitative characterization of surface features Surface roughness and fractal dimension Three-dimensional(3D)scanning Scanning electron micrograph(SEM)
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Three-dimensionally ordered macroporous SnO_2-based solid solution catalysts for effective soot oxidation 被引量:1
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作者 Cheng Rao Rui Liu +6 位作者 Xiaohui Feng Jiating Shen Honggen Peng Xianglan Xu Xiuzhong Fang Jianjun Liu Xiang Wang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第10期1683-1694,共12页
A series of three‐dimensionally ordered macroporous(3DOM)SnO2‐based catalysts modified by the cations Ce4+,Mn3+,and Cu2+have been prepared by using a colloidal crystal templating method and tested for soot combustio... A series of three‐dimensionally ordered macroporous(3DOM)SnO2‐based catalysts modified by the cations Ce4+,Mn3+,and Cu2+have been prepared by using a colloidal crystal templating method and tested for soot combustion under loose contact condition.XRD and STEM mapping results confirm that all the secondary metal cations have entered the lattice matrix of tetragonal rutile SnO2 to form non‐continuous solid solutions,thus impeding crystallization and improving the surface areas and pore volumes of the modified catalysts.In comparison with regular SnO2 nanoparticles,the 3DOM SnO2 displays evidently improved activity,testifying that the formation of the 3DOM structure can anchor the soot particulates in the macro‐pores,which ensures that the contact of the soot particles with the active sites on the 3DOM skeleton is more easily formed,thus benefiting the target reaction.With the incorporation of the secondary metal cations,the activity of the catalyst can be further improved due to the formation of more abundant mobile oxygen species.In summary,these effects are believed to be the major factors responsible for the activity of the catalyst. 展开更多
关键词 Three‐dimensionally ordered macroporous catalyst Soot combustion SnO2 solid solution Lattice doping Oxygen vacancies
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Role of 2-dimensional Doppler echo-cardiography in screening portopulmonary hypertension in portal hypertension patients 被引量:7
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作者 Hua, Rong Sun, Yong-Wei +4 位作者 Wu, Zhi-Yong Cheng, Wei Xu, Qing Cao, Hui Luo, Meng 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2009年第2期157-161,共5页
BACKGROUND: Portopulmonary hypertension (PPH) is difficult to recognize in the early and middle stages because it is frequently asymptomatic. As right ventricular function is impaired in patients with moderate and sev... BACKGROUND: Portopulmonary hypertension (PPH) is difficult to recognize in the early and middle stages because it is frequently asymptomatic. As right ventricular function is impaired in patients with moderate and severe PPH, any dramatic hemodynamic changes in liver transplantation or other procedures may result in death from pulmonary and cardiac events. In this study, we investigated the prevalence of PPH in patients with portal hypertension (PHT) mainly caused by hepatitis B virus, and evaluated the effect of 2-dimensional Doppler echocardiography (2D-ECHO) in screening for PPH. METHODS: One hundred and five PHT patients received transthoracic 2D-ECHO preoperatively, systolic pulmonary arterial pressure (SPAP, normal range <30 mmHg) and pulmonary acceleration time (PAT, normal range >= 120 msec) were measured to screen for PPH (positive result: SPAP >= 30 mmHg and/or PAT <100 msec). Subsequently, pulmonary hemodynamic parameters were measured by right heart catheterization (RHC) for definitive diagnosis of PPH. The results of the two methods were compared to assess the screening effect of 2D-ECHO. RESULTS: The prevalence of PPH in this study was 3.8% (4/105). About 90% (95/105) of patients had a detectable tricuspid regurgitation by 2D-ECHO and the mean SPAP was 27.7 +/- 5.9 mmHg. Twenty-two of these 95 patients had an SPAP >30 mmHg. The mean PAT of all patients was 140 23 msec and 5 were <100 msec. Twenty-two patients were screened out by 2D-ECHO and 4 were diagnosed by RHC. A positive significant correlation (r=0.55, P<0.01) was found between SPAP measured by 2D-ECHO and mean pulmonary artery pressure (MPAP) measured by RHC, and a weak but significant negative correlation (r=-0.27, P=0.005) existed between PAT and pulmonary vascular resistance (PVR). The sensitivity, specificity, agreement rate, positive predictive value and negative predictive value of the screening test were 100%, 82%, 83%, 18% and 100%, respectively. CONCLUSIONS: The prevalence of PPH in this study is lower than in Western countries. As a screening test, 2D-ECHO has very high sensitivity and negative predictive value. A negative test result can directly be used to exclude PPH, while a positive result should be confirmed by RHC. 展开更多
关键词 portopulmonary hypertension 2-dimensional Doppler echocardiography right heart catheterization PREVALENCE diagnosis
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二维半导体MoTe_(2)的极性调控与可重构电子器件中的应用
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作者 何小钱 芶晓霜 +3 位作者 孙富钦 赵占霞 王小伟 张珽 《上海大学学报(自然科学版)》 北大核心 2026年第1期44-53,共10页
以二维半导体二碲化钼(molybdenum ditelluride, MoTe_(2))的载流子极性调控及其在可重构电子器件中的应用为研究目标,构建了一种基于氧化钽(tantalum oxide,TaOx)/MoTe_(2)/六方氮化硼(hexagonal boron nitride, h-BN)异质结的双栅场... 以二维半导体二碲化钼(molybdenum ditelluride, MoTe_(2))的载流子极性调控及其在可重构电子器件中的应用为研究目标,构建了一种基于氧化钽(tantalum oxide,TaOx)/MoTe_(2)/六方氮化硼(hexagonal boron nitride, h-BN)异质结的双栅场效应晶体管(field-effect transistor, FET).利用栅极电场作用下TaOx/MoTe_(2)界面电荷的捕获/脱捕效应,实现了对双极性半导体MoTe_(2)载流子极性的调控.研究结果表明:通过调节控制栅极(control gate, CG)脉冲电压的极性与幅值,能够实现MoTe_(2)不同极性之间的可逆切换.负脉冲电压可以使MoTe_(2)的p型减弱, n型增强;而正向脉冲电压可使其p型增强, n型减弱.值得注意的是,这种调控效果会随着电压幅值的增大而显著增强.基于此方法,通过将两个串联的MoTe_(2)晶体管分别编程为n型和p型,实现了逻辑反相器功能.提出的利用界面电荷捕获效应实现二维半导体极性重构的方案,为功能可重构电子器件的实现提供了新思路. 展开更多
关键词 二维半导体 MoTe_(2) 极性调控 可重构电子器件 逻辑反相器
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Lump Solutions and Interaction Phenomenon for (2+1)-Dimensional Sawada–Kotera Equation 被引量:10
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作者 黄丽丽 陈勇 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第5期473-478,共6页
In this paper, a class of lump solutions to the (2+1)-dimensional Sawada–Kotera equation is studied by searching for positive quadratic function solutions to the associated bilinear equation. To guarantee rational lo... In this paper, a class of lump solutions to the (2+1)-dimensional Sawada–Kotera equation is studied by searching for positive quadratic function solutions to the associated bilinear equation. To guarantee rational localization and analyticity of the lumps, some sufficient and necessary conditions are presented on the parameters involved in the solutions. Then, a completely non-elastic interaction between a lump and a stripe of the(2+1)-dimensional Sawada–Kotera equation is obtained, which shows a lump solution is drowned or swallowed by a stripe soliton. Finally, 2-dimensional curves, 3-dimensional plots and density plots with particular choices of the involved parameters are presented to show the dynamic characteristics of the obtained lump and interaction solutions. 展开更多
关键词 lump solution interaction solution Hirota bilinear method (2+1)-dimensional Sawada–Kotera equation
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The Travelling Wave Solutions for (2+1)-dimensional AKNS Equation 被引量:3
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作者 程智龙 郝晓红 《Chinese Quarterly Journal of Mathematics》 2015年第3期323-329,共7页
Based on the travelling wave method, a(2 + 1)-dimensional AKNS equation is considered. Elliptic solution and soliton solution are presented and it is shown that the soliton solution can be reduced from the elliptic so... Based on the travelling wave method, a(2 + 1)-dimensional AKNS equation is considered. Elliptic solution and soliton solution are presented and it is shown that the soliton solution can be reduced from the elliptic solution. It also proves that the result is consistent with the soliton solution of simplify Hirota bilinear method by Wazwaz and illustrate the solution are right travelling wave solution. 展开更多
关键词 (2+1)-dimensional AKNS EQUATION SOLITON SOLUTION
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Interactions Between Solitons and Cnoidal Periodic Waves of the(2+1)-Dimensional Konopelchenko–Dubrovsky Equation 被引量:3
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作者 余炜沣 楼森岳 +1 位作者 俞军 杨铎 《Communications in Theoretical Physics》 SCIE CAS CSCD 2014年第9期297-300,共4页
The(2+1)-dimensional Konopelchenko–Dubrovsky equation is an important prototypic model in nonlinear physics, which can be applied to many fields. Various nonlinear excitations of the(2+1)-dimensional Konopelchenko–D... The(2+1)-dimensional Konopelchenko–Dubrovsky equation is an important prototypic model in nonlinear physics, which can be applied to many fields. Various nonlinear excitations of the(2+1)-dimensional Konopelchenko–Dubrovsky equation have been found by many methods. However, it is very difficult to find interaction solutions among different types of nonlinear excitations. In this paper, with the help of the Riccati equation, the(2+1)-dimensional Konopelchenko–Dubrovsky equation is solved by the consistent Riccati expansion(CRE). Furthermore, we obtain the soliton-cnoidal wave interaction solution of the(2+1)-dimensional Konopelchenko–Dubrovsky equation. 展开更多
关键词 CONSISTENT RICCATI expansion (2+1)-dimensional KD EQUATION soliton-cnoidal wave interaction solution
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Exact Solution of a(2+1)-Dimensional Anisotropic Star in Finch and Skea Spacetime 被引量:1
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作者 Piyali Bhar Farook Rahaman +1 位作者 Ritabrata Biswas Hafiza Ismat Fatima 《Communications in Theoretical Physics》 SCIE CAS CSCD 2014年第8期221-226,共6页
We provide a new class of interior solution of a(2+1)-dimensional anisotropic star in Finch and Skea spacetime corresponding to the BTZ black hole. We develop the model by considering the MIT bag model EOS and a parti... We provide a new class of interior solution of a(2+1)-dimensional anisotropic star in Finch and Skea spacetime corresponding to the BTZ black hole. We develop the model by considering the MIT bag model EOS and a particular ansatz for the metric function grrproposed by Finch and Skea [M.R. Finch and J.E.F. Skea, Class. Quantum.Grav. 6(1989) 467]. Our model is free from central singularity and satisfies all the physical requirements for the acceptability of the model. 展开更多
关键词 (2+1)-dimensional ANISOTROPIC STAR Finch and Skea SPACETIME
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Various Types of Kink and Bright Resonant Soliton Solutions for the (2+1)-Dimensional Double sine-Gordon Equation 被引量:1
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作者 林机 黄光侨 陈伟雄 《Communications in Theoretical Physics》 SCIE CAS CSCD 2015年第7期59-66,共8页
The algebraic mapping relations between the(2+1)-dimensional double sine-Gordon equation and the cubic nonlinear Klein–Gordon equation are constructed. Many new types of two-dimensional resonant kink, bright soliton ... The algebraic mapping relations between the(2+1)-dimensional double sine-Gordon equation and the cubic nonlinear Klein–Gordon equation are constructed. Many new types of two-dimensional resonant kink, bright soliton and solitoff solutions are obtained, such as broken line shape, "V" shape, "snake" shape and "M" shape solitary waves,Zigzag-curve type, "ω" shape, peroidic-curve type, oscillatory Arch-type and parabolic shape bright soliton waves. We also investigate the propagating properties of some soliton solutions. 展开更多
关键词 (2+1)-dimensional DOUBLE SINE-GORDON equation mapp
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Painlevé Property and Exact Solutions to a (2+1) Dimensional KdV-mKdV Equation 被引量:1
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作者 Yuqing Liu Fang Duan Chao Hu 《Journal of Applied Mathematics and Physics》 2015年第6期697-706,共10页
A (2 + 1) dimensional KdV-mKdV equation is proposed and integrability in the sense of Painlevé and some exact solutions are discussed. The B?cklund transformation and bilinear equations are obtained through Painl... A (2 + 1) dimensional KdV-mKdV equation is proposed and integrability in the sense of Painlevé and some exact solutions are discussed. The B?cklund transformation and bilinear equations are obtained through Painlevé analysis. Some exact solutions are deduced by Hirota method and generalized Wronskian method. 展开更多
关键词 (2+1) dimensional KdV-mKdV Equation Painlevé Property Backlund Transformation Bilinear Equation Wronskian Method
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基于Cu掺杂三维有序大孔SnO_(2)的H_(2)S气敏性能研究
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作者 万子谦 胡坤 +1 位作者 柏凌 王明松 《传感器与微系统》 北大核心 2026年第3期51-56,共6页
采用溶剂热蒸发法自组装的胶体晶体为硬模板,通过牺牲模板法制备具有不同Cu掺杂量的三维有序大孔SnO_(2),研究了不同Cu掺杂量下大孔SnO_(2)对H_(2)S的气敏性能变化,并通过热脉冲辅助法改善了低温下传感器的恢复特性。表征结果证实了SnO_... 采用溶剂热蒸发法自组装的胶体晶体为硬模板,通过牺牲模板法制备具有不同Cu掺杂量的三维有序大孔SnO_(2),研究了不同Cu掺杂量下大孔SnO_(2)对H_(2)S的气敏性能变化,并通过热脉冲辅助法改善了低温下传感器的恢复特性。表征结果证实了SnO_(2)具有周期性密排堆积的三维有序多孔结构,Cu离子的掺杂并未对其有序大孔结构产生破坏,但会导致SnO_(2)发生晶格畸变并产生更多的缺陷,进而影响传感器的气敏性能。气敏测试结果表明:掺杂量为0.5%的SnO_(2)表现最佳,在50℃的最佳工作温度和热脉冲辅助下,对体积分数为5×10^(-6)和10×10^(-6) H_(2)S的气敏响应高达72.9和187.3,并表现出良好的选择性、抗湿性和长期稳定性。不仅为多孔材料的设计提供了方案,并且为提高敏感材料的低温气敏响应提供了新思路。 展开更多
关键词 三维有序多孔 Cu-SnO_(2) H_(2)S 热脉冲
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Exotic interactions between solitons of the (2+1)-dimensional asymmetric Nizhnik-Novikov-Veselov system 被引量:3
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作者 戴朝卿 周国泉 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第5期1201-1208,共8页
Starting from the extended tanh-function method (ETM) based on the mapping method, the variable separation solutions of the (2+1)-dimensional asymmetric Nizhnik Novikov Veselov (ANNV) system are derived. By fur... Starting from the extended tanh-function method (ETM) based on the mapping method, the variable separation solutions of the (2+1)-dimensional asymmetric Nizhnik Novikov Veselov (ANNV) system are derived. By further study, we find that these variable separation solutions are seemingly independent of but actually dependent on each other. Based on the variable separation solution and by choosing appropriate functions, some novel and interesting interactions between special solitons, such as bell-like compacton, peakon-like compacton and compacton-like semifoldon, are investigated. 展开更多
关键词 extended tanh-function method 2+1)-dimensional ANNV system exotic interactions between solitons
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Symmetry Analysis and Conservation Laws to the(2+1)-Dimensional Coupled Nonlinear Extension of the Reaction-Diffusion Equation 被引量:3
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作者 陈俊超 辛祥鹏 陈勇 《Communications in Theoretical Physics》 SCIE CAS CSCD 2014年第8期173-182,共10页
In this paper, a detailed Lie symmetry analysis of the(2+1)-dimensional coupled nonlinear extension of the reaction-diffusion equation is presented. The general finite transformation group is derived via a simple dire... In this paper, a detailed Lie symmetry analysis of the(2+1)-dimensional coupled nonlinear extension of the reaction-diffusion equation is presented. The general finite transformation group is derived via a simple direct method,which is equivalent to Lie point symmetry group actually. Similarity reduction and some exact solutions of the original equation are obtained based on the optimal system of one-dimensional subalgebras. In addition, conservation laws are constructed by employing the new conservation theorem. 展开更多
关键词 (2+1)-dimensional COUPLED nonlinear REACTION-DIFFUSION equation LIE symmetry invariant solutions optimal system conservation LAWS
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New periodic wave solutions, localized excitations and their interaction for (2+1)-dimensional Burgers equation 被引量:2
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作者 马红彩 葛东杰 于耀东 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第12期4344-4353,共10页
Based on the B/icklund method and the multilinear variable separation approach (MLVSA), this paper finds a general solution including two arbitrary functions for the (2+1)-dimensional Burgers equations. Then a cl... Based on the B/icklund method and the multilinear variable separation approach (MLVSA), this paper finds a general solution including two arbitrary functions for the (2+1)-dimensional Burgers equations. Then a class of new doubly periodic wave solutions for (2+l)-dimensional Burgers equations is obtained by introducing appropriate Jacobi elliptic functions, Weierstrass elliptic functions and their combination in the general solutions (which contains two arbitrary functions). Two types of limit cases are considered. Firstly, taking one of the moduli to be unity and the other zero, it obtains particular wave (called semi-localized) patterns, which is periodic in one direction, but localized in the other direction. Secondly, if both moduli are tending to 1 as a limit, it derives some novel localized excitations (two-dromion solution). 展开更多
关键词 2+1)-dimensional Burgers equation mutilinear variable separation approach periodicwave solutions localized excitation
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